One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,8)(4,6)(5,7)(9,10,15,18)(11,19,12,16)(13,14,17,24)(20,23,22,21)(26,31)(27,34)(33,38)(35,40)(1,3,5,4)(2,6,7,8)(11,12)(16,19)(20,22)(21,23)(25,26,30,31)(27,29,34,32)(28,33,37,38)(35,36,40,39)(9,11,15,12)(10,16,18,19)(13,20,17,22)(14,21,24,23)(25,27)(26,29)(28,35)(30,34)(31,32)(33,36)(37,40)(38,39)(2,7)(6,8)(9,12,15,11)(10,16,18,19)(13,22,17,20)(14,21,24,23)(25,27)(26,32)(28,35)(29,31)(30,34)(33,39)(36,38)(37,40)(1,4,5,3)(2,8,7,6)(9,13,15,17)(10,14,18,24)(11,20,12,22)(16,21,19,23)(25,28,30,37)(26,33,31,38)(27,35,34,40)(29,36,32,39)(1,2)(3,6)(4,8)(5,7)(9,14)(10,17)(11,21)(12,23)(13,18)(15,24)(16,22)(19,20)(25,29,30,32)(26,34,31,27)(28,36,37,39)(33,40,38,35)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.